In his commentary on old King Solomon’s need to sleep with a maiden hot enough to keep him warm and holy enough not to arouse his lust, Saint Jerome has this to say:Who is this Shunammite, both wife and virgin, so hot that she could heat the frozen, so holy that she did not rouse to lust him whom she had warmed?He goes on to explain that wisdom is the maiden who comes to embrace us in old age:In the aged, nearly all the bodily powers wear out,and wisdom alone increases;all the others decrease:such as fasting, watching, sleeping on the floor,travelling from place to place,entertaining travellers,defending the poor,being instant and persevering in prayer,visiting the sick,manual labour for the providing of alms.And without prolonging my discourse,all those things that are done through the body diminishas the body breaks down.I do not mean to say that wisdom,which in many of the aged declines into senilityis lacking in the young or in those of maturer age;that is, in those who by toil or earnest zeal,by holiness of life,and by frequent prayer to the Lord Jesus,so seek after knowledge:but I mean that many who are young in bodyhave a battle to fight,and amidst the incentives to sinand the temptations of the flesh,wisdom is smothered as fire is in green wood,so that its flame cannot leap forth.But when old age comes upon thosewho have spent their youth in acquiring knowledgeand have exercised themselves in the law of the Lord day and night,then they become more learned with age,more skilled through experience,wiser as time goes by,and they reap the most sweet fruit from their diligence.Saint Jerome, Letter to Nepotian

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How to Be Both Hot and Holy in Old Age